Casein Content of Buffalo and Cow Milk

The Casein contents of buffalo milk & cow milk are respectively:

Correct Answer: Buffalo 4.3% & Cow 3%

Buffalo milk contains 4.3% casein and Cow milk contains 3% casein. Buffalo milk has significantly more casein than cow milk, which is why buffalo milk is preferred for making khoa, paneer, and other casein-rich products.

Casein in Milk

• Casein is present in milk as a colloidal suspension of calcium-caseinate-phosphate complex.
• It constitutes approximately 80% of total milk protein.
• Casein exists in three forms: α, β, γ casein.
• α-casein has two components: αs-casein (calcium-sensitive) and K-casein (calcium-insensitive).
• K-casein acts as a protective colloid, stabilizing casein micelles.
• Rennet (chymosin) acts on K-casein → destabilizes micelles → milk coagulates (basis of cheese making).

Casein and White Colour

Casein's large colloidal micelles scatter all wavelengths of visible light equally → milk appears white. Buffalo milk is whiter than cow milk partly due to higher casein content.

Why Other Options Are Wrong

• 3% & 4.3% → values are reversed (buffalo and cow swapped).
• 4% & 3% → 4% is close for buffalo but 4.3% is the correct value.
• 5% & 7% → fabricated values; no standard reference supports these.